No way a single 970 or 980 can play at max settings and 1600p on some of the demanding games out there. The question you have to ask yourself is if it is worth spending $300+ so you can turn a few settings up higher in a handful of games that you own. These games are still fun at less than Ultra/max settings.
With your Bottlenecking. I would look at CPU Ram speeds and harddrive
I have a Intel i7 4790k
16GB 2666mhz 8GB shared with GPU
I run one GTX970 playing games at 2160 in ultra 36fps and upwards
I have the Palit Jetstream 970
It overclocks like a mother base core 1286mhz Boost 1536mhz
Ram 8240mhz
36 FPS with that PC!? well.. 4K at ultra must be demanding in some games. My brother has a similar PC and runs games at 1080p (like Lords of the Fallen) with over 100 fps.
allwaysquality2011 :
With your Bottlenecking. I would look at CPU Ram speeds and harddrive
I have a Intel i7 4790k
16GB 2666mhz 8GB shared with GPU
I run one GTX970 playing games at 2160 in ultra 36fps and upwards
I have the Palit Jetstream 970
It overclocks like a mother base core 1286mhz Boost 1536mhz
Ram 8240mhz